


Birthday Gift

by losing_sanity_fast



Series: the Zoldyck political clan [5]
Category: Hunter X Hunter
Genre: Aged-Up Character(s), Aged-Up Gon Freecs/Killua Zoldyck, Anal Plug, Anal Sex, Don't copy to another site, Don't repost, Fluff, Fluff and Smut, M/M, Mild Kink, Modern AU, Oral Sex, Sex Toys, Smut, a bit of bondange, they're 22 here unless i'm compeltely forgetting the timeline
Language: English
Status: Completed
Published: 2019-10-22
Updated: 2019-10-22
Packaged: 2020-12-28 16:24:22
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,710
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21139649
Author URL: https://archiveofourown.org/users/losing_sanity_fast/pseuds/losing_sanity_fast
Summary: Killua has a birthday and Gon has a theory to test, plus he really needs to distract himself.





	Birthday Gift

**Author's Note:**

> It seems that whenever I get writer's block I write a sextra for this universe, it's a fact of my life now I guess. And they get more explicit with time XD.  
This works well as a one shot, so don't worry, you don't have to read the whole series to get it. there are a few references to hcs from this au and series, but they don't make anything confusing, i feel. for those who read the series, this goes just before the 9th chapter of the long fic, i mean literally about 30-40 days earlier. 
> 
> Beta read by the lovely and patient [sweete_serendipity](https://archiveofourown.org/users/sweete_serendipity/pseuds/sweete_serendipity) and [sub_divided](https://archiveofourown.org/users/sub_divided/pseuds/sub_divided). They're both wonderful people and amazing writers so check out their stuff!
> 
> _I'm not a native speaker so the language is what it is._

* * *

“You didn’t have to buy me anything,” Killua tentatively touched the present covered in star-patterned wrapping paper. “You already organised that long weekend of bouldering, and then you invited everyone to the restaurant.”

“I know,” Gon gently stroked his hand. Killua was right, he did go all out on this birthday. “But I wanted to.”

_ It’s as much for you as it is for me _, he thought, but smiled instead of saying it. Killua was going to understand it soon enough. 

Killua sighed. He worried, Gon knew that all too well. Gon was leaving for the Olympics in a few weeks and Killua didn’t want to distract him from his preparations. Actually the truth was Gon needed to occupy his mind in some other ways not to overtrain himself and burn out before the Games. Besides after the Olympics he was planning to propose and that stressed him out, too. Killua’s birthday served as a perfect distraction. 

He pushed the present towards his boyfriend, eager to see Killua’s reaction.

The cute paper came off revealing a plastic box with a pair of leather handcuffs and a few lengths of chain to connect them. 

Killua licked his lips nervously and slowly opened the box. His face went pink. 

Gon expected this, Killua found it hard to talk about these things. But his eagerness to unpack the cuffs spoke volumes as to what he was actually thinking. 

Once he pried the plastic open he took the purple leather and turned it around in his hands. He ran a finger over the rainbow fur inside. Then he examined the chains, pulled on them a bit, testing their strength.

Gon let him take it all in, he had done the same after they came in the mail, he wanted to make sure they were solid.

“They are…” Killua started, he tried to look at Gon, but failed. Instead he just took Gon’s hand. “Perfect, they’re perfect.” He leaned over the table to kiss Gon.

Their dynamic amused Gon a bit but also filled him with pride. Few couples he knew could boast this level of understanding. Killua rarely managed to talk about his feelings or desires, but sometimes he surprised Gon with something, like lace lingerie or a cheerleader uniform for celebrating Gon’s wrestling victories. The latter came with a new music number each time it was donned and Killua strictly forbade Gon to speak about it to anyone. Not the outfit, Killua had said, but the dancing. Not that Gon would share the details of their sex life with anyone, but this very specific concern of Killua’s was just too cute. 

Killua avoided asking for anything and Gon knew where that came from. Killua presented a cocky exterior to the world at large, confident in his skills and knowledge, snarky and witty. He even presented that front to Gon most of the time, unless it came to their relationship. There Killua clung to some ideas about not being worthy of what they had and these concerns had only partially subsided with time, which led to him feeling self-conscious. Gon didn’t mind it that much, it gave him a challenge. He needed to concentrate and observe his boyfriend. Reading him wasn’t that hard in the end. And when he managed to figure Killua out it gave him an incredible rush. Like when he realised Killua enjoyed being held down. That knowledge made Gon suspect that his boyfriend might appreciate some more restraining. 

The kiss turned into Killua straddling Gon on the chair. That led to Gon’s shirt landing on the floor, soon followed by Killua’s cute top. 

Killua reached for the cuffs and fastened one around his wrist. Gon watched, it looked really nice against the pale skin. 

“Which one, do you think?” Killua asked considering the chains. The shortest one had only three links, the longest probably 20 centimetres clearly meant for cuffing someone to something. 

Gon looked around, he had never really paid much thought to their bed but suddenly it looked very unsatisfactory. It had no posts and no headboard, just a mattress from Ikea on a basic flat frame with a few drawers in it. Practical for storage in their tiny studio, not for restraining his boyfriend and fucking him sensless. An issue Gon hadn’t even considered while choosing the gift. 

“The shortest one,” he said picking the chain up and attaching it to the cuff on the table then the one around Killua’s wrist. “I have nothing to cuff you to, unfortunately.” He kissed Killua’s blushing cheek and then indicated that they should get up. He led his boyfriend to the bed. “I’ll figure something out for next time,” he said unzipping Killua’s jeans and pulling them down together with the briefs, exposing a partial erection. “So for today I’ll just cuff your hands behind your back.” He circled Killua and pulled his arms until the wrists met above the bare ass. Then he fastened the other cuff. He checked if it wasn’t too tight or too loose. 

He could hear Killua breathe deeper and whisper Gon’s name. Killua got like this when Gon held him down, so everything was on the right track. 

Gon ran his fingers up and down Killua’s arms and kissed the nape of his neck. That elicited enticing sighs. Gon’s hands travelled to Killua’s chest and slid down to his stomach. He could feel Killua shiver. He gently teased Killua’s cock, now rock hard, to get the pretty soft moans his boyfriend produced when touched.

Then he remembered something. “If you stop liking it tell me,” Gon said.

“I will.” 

Gon blew some air onto Killua’s neck and then proceeded to kiss it. Whether Killua would really protest Gon wasn’t sure. It had never happened before, but that only made Gon more cautious about monitoring Killua’s face. 

“Anyway,” Gon stepped away and opened a drawer. He took out the lube and pondered for a moment, then picked a nice plump butt plug. The set of toys was the first of the things Killua got for them in his shy way. The box had just one day appeared on Gon’s desk, no comment. Later Killua admitted to buying it when they started dating, because he read up online how to get ready. It was such a Killua move it made Gon laugh, but also love him more. The toys did come in handy quite often. 

“Warm this up for me.” He put the metal plug in Killua’s hands, making sure his fingers were wrapped tightly around it, so he wouldn’t drop it. 

“You’re so thoughtful.”

“I’m just planning to take my time with you, but I want you to be nice and ready. Now legs apart.” Killua heeded the demand. “A bit more.” 

Then Gon pushed Killua forward, forcing him to bend. 

“We’re doing yoga now?” Killua teased. He was very limber, so his head easily found itself at the same level as his knees. At the same time he was gently rubbing his hands to warm up the metal. 

“You told me there was rope play in yoga, when you went with Alluka and Palm a few times.” Gon gently stroked the exposed buttocks, the view turned him on like hell, but he needed to take it slow. He poured some lube and warmed it up by rubbing his fingers.

“There’s stretching on ropes it’s not as sexy as it sou..ounds.” Killua sighed mid sentence when Gon’s fingers stroked his hole. 

He inserted a finger and Killua exhaled. Gon played longer than he expected, it was nice to watch Killua maintain the position while very aroused, especially that the restrained arms did not help with balancing. Finally he inserted the plug and watched Killua straighten up. 

He walked around Killua, taking him in, until they ended up face to face. 

“I love looking at you.”

“You can’t say such things.” Killua blushed. 

Gon kissed him. “You tell me you like the way I look all the time.”

“Yes, because it’s you, you’re perfect, besides I don’t do it in moments like this.” 

They were looking each other in the eye and it made Gon shiver. He pulled Killua into another kiss. 

“You sometimes say it after sex, when you think I’m asleep.”

Killua smiled in a cheeky way. “Well I’m allowed, especially when you should be asleep and not listening. Don’t pretend to sleep you weirdo.”

“Seems unfair.” He said. “Either way. You’re too tall, so on the bed.”

Killua giggled and carefully got on then gazed at Gon expectantly, unsure what to do next. 

“What’s most unfair,” he said, “is that you still have your pants on.” Killua looked suggestively at Gon’s crotch. “It must be uncomfortable.” He waddled on his knees closer to the edge of the bed, then he just sat on his feet. 

“A bit.” Gon admitted, the erection was pushing hard against the fabric. 

“Let me kiss it to make it better.” Killua licked his lips invitingly. 

Gon couldn’t stop a small smirk. He was hoping for this and his thirsty boyfriend did not disappoint. Killua dropped his eyes coyly and bit his lower lip. This was actually a pose, not a real sign of him being self-conscious. The lack of blushing indicated that. A while back he hadn’t been able to tease during sex, or joke, Gon loved to see him come out of his shell little by little. 

“That’s the best medicine.” Gon unzipped his joggers and let them fall to the floor, then he helped the boxers a bit so they would follow. He stepped out of the puddle of fabric and stood with his dick proudly in front of Killua’s face. 

Killua kissed the tip and twisted his head to get his tongue under the cock. Without hands it took considerable skill. Luckily their mattress was rather firm, so it helped Killua to keep upright while he wiggled on the bed lapping his tongue along Gon’s dick. Gon tried to help him by angling his hips. Soon enough Killua took the dick into his mouth and it got a bit easier. They found a mutually comfortable position and Gon could just enjoy the show. Killua’s mouth travelled up and down his cock, taking in a bit more each time. Killua was glancing up at him from time to time, clearly enjoying himself. Gon’s breathing picked up, he started to moan. 

“Damn, Killua, this feels so good.” He managed to say in between the sighs. 

Killua looked up and grinned, there was mischief in his eyes. And with a smooth motion he took the whole length of Gon’s dick in his mouth. He had learned this move about a year earlier and used it to his advantage ever since. Gon liked victory blow jobs, and he did win often so Killua had plenty of opportunities to practice. 

“Oh, god,” Gon moaned. It felt amazing. And looked even better. Killua’s face was pressed to Gon’s pelvis, and further down the cuffed hands balled into fists. While the muscles of the twisted arms were tense with effort.

Gon was losing control and he knew that Killua did it on purpose. 

“Yes, cuff me and I’ll be a good boy, I’ll do anything you want,” Gon said with a hint of irony trying to remain in control of his body and mind. He put his hand firmly on Killua’s head and reluctantly moved away, out of reach of the eager lips. “I didn’t prep you to come in your mouth now.”

Killua looked at him and pouted a bit. 

“Really?” Gon bent and cupped the cute sulky face. “Don’t you want me to fuck you so hard that you’ll come without me touching your dick even once?” He whispered. “Like the good boy you are, who always comes for me when I ask.” He finished and pecked Killua on the nose, then looked him in the eye. 

Killua averted his gaze almost instantly. He was blushing and shivering. This was real, not an act: excitement, shyness, and a bit of self-consciousness. Gon wondered if he could actually get Killua to come just by talking to him like this, but he felt it would be mean to try. 

Instead Gon pushed Killua, who fell onto his side on the bed. He tried to scramble back to his knees, pulling on the cuffs which held him nicely constrained. Gon jumped on the bed and was above Killua in a split second. 

“Now I’ll have my way with you,” Gon said while almost lying on top of Killua when he reached for the lube.

Killua went still and looked at Gon with very obvious anticipation. Gon sat up on the bed and paused for a moment, considering his options. Usually in these situations, he twisted Killua’s arm behind his back, but he was already tied up, so that wasn’t necessary. He moved Killua so he was on his knees bent forward, the belly pressing against the thighs, with his pale blond hair touching the sheets. Gon stroked his spine, gently outlining each protruding bone. 

“I’ll change the position of your arms a bit, okay?”

“Yes.” 

He barely heard Killua’s voice muffled by his knees. 

Gon detached one end of the chain and bent Killua’s arm up, placing his hand on the shoulder blade, then he positioned the other hand next to it and reattached the chain. Killua breathed in deeply.

“Oh, fuck,” Killua whispered.

“Is this fine? Not uncomfortable?”

“Wrong question, Gon.”

_ Yeah, you like uncomfortable, how could anything about this position be comfortable. _

“Right, sorry.”

He lubed his own dick, then for a moment he teased the plug stretching Killua’s ass. Killua was balling his fingers into a fist and then outstretching them again, his breathing was fast and shallow. 

“Please…” he whispered a few times when Gon was playing with the metal toy. 

Gon obliged and pulled out the plug, on his own terms, he liked to have Killua like that, a needy mess. He lifted Killua’s hips and slowly pushed in, eliciting more quiet desperate pleas. 

Killua’s head was hanging a few centimetres above the bed and Gon knew he had to be careful to keep him above the mattress at all times. He gripped Killua’s hips with both hands, there were going to be marks, but in all honesty Killua was probably going to be happy about them, as much as he enjoyed the bruising on his forearms when Gon held him down. 

He rocked them gently, sliding in and out. Slowly at first, not heeding the needy wishes coming from his boyfriend. He wanted to find the right angle first, before he commited to more intense fucking. After all he promised Killua a hands-free orgasm. 

When he felt Killua tremble, moan and cry out under him, he knew he found the right spot. He picked up the pace and went in full length. 

The pretty noises Killua made, all for him. It felt like applause after he scored a point. But for this to be a win he still had to work a bit. A tall order as he was pretty close himself. 

He leaned forward as much as he could without toppling them over. He was fully in, pressed to Killua’s ass and lower back. 

“Come for me, kitty cat.” He accentuated the rather stern order with deep strong thrusts. “Come for me.” 

That was what his boyfriend needed to be pushed over the edge. He orgasmed with a long cry of Gon’s name. The sudden tightening of muscles got Gon where he wanted, too. 

With his final ounce of strength he straightened up and reluctantly pulled out. He gently laid his boyfriend on the bed and unclipped the chain to let him stretch his arms out. Then he spooned him. They were both sweaty and panting heavily. Gon felt his arms and shoulders were going to hurt the next day from the exertion. Typical after a win.

“You’re too good for me, it’s crazy,” Killua whispered.

Gon smiled. “Same,” Gon kissed his neck. “You’re too good.” 

Killua pulled Gon’s hand closer and kissed his fingers. Gon expected him to protest the confession. 

“You’re amazing, Gon,” he said instead. “This is the best gift ever.” 

* * *

**Author's Note:**

> I hope you enjoyed it. 
> 
> As always I couldn't chose the title for this thing. here are some other options I considered. tell me if you like them more, or maybe you have some better suggestions XD  
1\. cuffs  
2\. we need a new bed  
3\. this bed sux  
4\. killua is a good boy  
5\. other ideas??


End file.
